Method of manufacturing wide-band gap semiconductor device

Abstract

A wide-band gap semiconductor device and a method of manufacturing the same are provided. The wide-band gap semiconductor device of the disclosure includes a substrate, an epitaxial layer, an array of merged PN junction Schottky (MPS) diode, and an edge termination area surrounding the array of MPS diode. The epitaxial layer includes a first plane, a second plane, and trenches between the first plane and the second plane. The array of MPS diode is formed in the first plane of the epitaxial layer. The edge termination area includes a floating ring region having floating rings formed in the second plane of the epitaxial layer, and a transition region between the floating ring region and the array of MPS diode. The transition region includes a PIN diode formed in the plurality of trenches and on the epitaxial layer between the trenches.

What is claimed is: 
     
       1. A method of manufacturing a wide-band gap semiconductor device, comprising:
 forming an epitaxial layer on a substrate, wherein the epitaxial layer includes a first plane: 
 removing a portion of the epitaxial layer to form a second plane around the first plane and a plurality of trenches between the first plane and the second plane; 
 forming an array of merged PN junction Schottky (MPS) diode in the first plane of the epitaxial layer, wherein the array of MPS diode comprises a plurality of first p+ doping regions in the epitaxial layer to form a PN junction between the epitaxial layer and each of the first p+ doping regions, and a plurality of Schottky diodes with the epitaxial layer among the first p+ doping regions by disposing a Schottky metal layer on the epitaxial layer; 
 forming a PIN diode on the plurality of trenches and on the epitaxial layer between the trenches, wherein the PIN diode comprises a second p+ doping region; and 
 forming a plurality of floating rings in the second plane of the epitaxial layer, wherein the plurality of floating rings is a plurality of third p+ doping regions, and the first p+ doping regions, the second p+ doping region, and the third p+ doping regions are implanted simultaneously. 
 
     
     
       2. The method of manufacturing the wide-band gap semiconductor device of  claim 1 , wherein the step of forming the array of MPS diode comprises forming the Schottky metal layer to form the plurality of Schottky diodes with the epitaxial layer among the first p+ doping regions. 
     
     
       3. The method of manufacturing the wide-band gap semiconductor device of  claim 2 , wherein the step of forming the Schottky metal layer comprises extending the Schottky metal layer to cover sidewalls and bottoms of the trenches and on the epitaxial layer between the trenches. 
     
     
       4. The method of manufacturing the wide-band gap semiconductor device of  claim 1 , wherein the step for forming the first p+ doping regions, the second p+ doping region and the third p+ doping regions is one-step implantation or two-step implantation.